how do you manage your O / M 365 licenses for a large organization?

[DaveTheTeamsGuy]

I'm looking for how other admins manage their Office / Microsoft licensing, especially for large organizations where people frequently move personas / work types. 

Do you automate it?  How?  I know you can use dynamic group licensing, but how do you get the right users matched up with the right licenses?

Do you just buy the top tier license"?  If so, have you found that a higher license cost is cheaper than trying to manage those licenses?  How did you do your comparison? 

Do you use a third party service?  If so, which services have you had success with? 

Trying to get some ideas on how to streamline this process.

Thank you!

[#2]

There's no single correct answer here, just do what works best for your organization. Group-based licensing (with or without dynamic membership) or good old PowerShell-based scripts allow for a lot of customizability, and are able to address most scenarios. The problem they dont solve is give you a good overview of usage, and this is where third party tools usually add some value. That, and management for more complex scenarios, BUs, multi-tenant, etc. Cost optimization too.
Asking for recommendations on that front is asking to turn the thread into a vendor spam fest though, just do some research online :)